Ur

Ur was an important Sumerian city-state in Mesopotamia which existed from 3800 BC to 500 BC. It was founded by the Ubaidians as a coastal city at the mouth of the Euphrates on the Persian Gulf, and, in around 2500 BC, Mesannepada became its first king. From 2030 BC to 1980 BC, Ur was the largest city in the world, and it had a population of 65,000 people. Its empire fell in 1940 BC to the Elamites, and it came to be ruled by a succession of empires. It started to decline after the Persian conquest of Babylon in 530 BC, and drought, changing river patterns, and the silting of the outlet to the Persian Gulf caused its abandonment by 500 BC.